Simulation Project: Production Line Wasted Outputs



Case Study:

Production Engineers of the group are planning to perform a quality improvement project aimed at controlling the output of machine A. In order to run this project, the engineers designed a simulation experiment to establish a quality procedure in which the production would be ceased if Machine A started producing a sequence of flawed products. After stopping production, they could re-set up the machine and maintain it for the next round. The project is also aimed at supporting the maintenance planning department to estimate the next possible maintenance or breakdown interval.  

The machine performance has been measured in a different project. The project was interested in sampling and calculating the number of "ok", "rework" and "waste"  outputs per 10000 end-products. The observation shows that  90% of the outputs are flawless, 5% need rework, and 1% are wasted. 

Solutions:

Based on the information, they can run a simulation project in which the number of flawless products before the machine started to produce 4 defective products in a row, could be estimated. They run the simulation for 10 observations. The results are as the graph below.  For example, we can clearly see that the machine starts to produce the first set of defective products after continuous production of 4000 production elements, and the second set after 24000 continuous production processes, and so on. 



gist.GitHub Code



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